4
8.
Additional Notes – Following Site Inspection June 07.
Usage of the scrubber is currently un-quantified so inspection and testing routines should be
more frequent until appropriate routines are established. It was noted during the site
inspection that large quantities of solids were being deposited in the scrubber and it may be
solid deposition rather than chemical levels that determine flushing cycles.
The scrubber is mainly designed to deal with HCL gas which is easily water soluble. Precise
control of chemical concentrations and levels is not required. HCL dissolved in fresh water
turns it acidic, the more acidic the recirculation liquor in the scrubber the less efficient it will be
at the removal of HCl. Addition of alkali caustic soda reacts with the HCL in the liquor to
lengthen the time the scrubber remains efficient. Continuous addition of more caustic will
cause salt build-up and blocking of the scrubber, the scrubber content should be drained and
refilled with fresh solution to prevent this. Monitoring of the state of the liquor can be simply
carried out using litmus paper or equivalent.
The caustic solution concentration is not critical, we would recommend below 15% and state
5% as a nominal value.
Caustic soda reacted with HCL gives common salt, provided the pH is neutral the scrubber
liquor should be fit to dispose down the drain, however this takes no account of any other by-
products of the furnace. This should be determined by chemical testing.
The problem of scaling due to hard water was raised. Caustic solution will exacerbate this
problem. However the scrubbing system is resistant to chemical attack so can be descaled
using a mild acid solution (or allowing the scrubber liquor to become acidic).
For the purposes of cleaning, the inside of the scrubber can be pressure washed. The mist
eliminator pad should be gently manipulated to aid solid break up and then pressure washed.
Summary of Contents for FSSR1
Page 1: ...Issue 1 02 07 FSSR1 Venturi Scrubber Unit OPERATOR S MANUAL ...
Page 7: ...1 Appendix 1 Scrubber Layout ...
Page 8: ...A3 ...
Page 9: ...Appendix 2 Operating and Maintenance Instructions for Pump ...
Page 10: ...Read this manual before use of product MD SERIES Instruction Manual IWAKI Magnetic Drive Pump ...